Physical activity, exercise, playing certain games and outdoor activities are important parts of a person's life. However, they are not possible all the time since the appropriate place is not available everywhere. One problem with making exercise places is that for making it, nature has to be disturbed and grass is destroyed and eliminated to be replaced with cement or asphalt (to make a play ground such as tennis court) or similar hard things. This application introduces play grounds and decks that are to be set up on temporary basis. They are designed to be placed on top of grass, over the driveways, above the pools, on uneven places, etc, so that nature and the underlying ground would not be disturbed permanently. They also have other uses such as setting up a tent safely and enjoying from such units in any possible way.